This invention relates generally to a seating system in which the slope of its understructure is variable to provide variable sight lines for multiple stadium/arena configurations. More particularly the treads of the seating system are pivotable such that the height of the risers are variable between different sloping configurations.
There are a number of known telescopic seating systems having variable risers in which each row of seats is structured as to be independently telescopic for both maintaining a predetermined slope of the seating system and establishing the preferred riser height. For example, Japanese patent 4-277267 discloses in its FIGS. 6 and 7 such a variable riser telescoping platform seating system as does French patent 2687713. Japanese patent 2-153171 discloses a variable sloping seating section with the treads being maintained horizontal.
French patent 2,306,319 discloses a tiered seating system for mobile theaters in which the slope of the understructure beams is varied, and the treads are adjustable as to remain substantially horizontal irrespective of the inclination of the structure.
The known prior art systems are, however, of generally complex structure and require many moving parts which therefore bring into question the reliability and economy of such systems.